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Ccoverting oil steam boiler to gas, and what else?


I've read quite a few previous posts, but they seemed either out of date or not quite pertinent to our situation. We are considering converting our oil steam boiler to natural gas. Natural gas has recently become available to us (we are the very last house on the line), and our oil-fired boiler has been pronounced moribund. It's not that old -- maybe 14 years -- and a very good brand, so I have to accept that poor maintenance is to blame. We have very hard water, and I sometimes let several months go by without purging the boiler. (Sorry. We knew nothing about radiators or steam at all when we bought the house 10 years ago.)

If we have to replace the boiler anyway, it seems prudent to consider converting to natural gas. I checked the fuel comparison chart recommended here, and it appears that natural gas is about a third of the price of fuel oil in our area per Btu. Gas boilers are more efficient, and I believe we may be eligible for a tax credit on that account.

We also have an oil-fired water heater. We'd need to switch that too, I guess, but I'm very confused about the pros and cons of indirect water heating from the boiler versus a stand-alone gas water heater. I thought indirect was a good idea when I first heard of it, but I've since heard that it adds to the gas costs.

Re: Ccoverting oil steam boiler to gas, and what else?


Yes, glad to see natural gas service has finally arrived at your location.

I've read your past posts from 2008, along with the other respondents and am in agreement with most of what was said in those past posts, specifically about going with an indirect hot water heater, and determining if your exterior walls have insulation.

This is a big house, making it costly to heat.

I would hate to see you pay $6k to $8k for a new gas-fired steam boiler & have the same problems with daily maintainence and suffer another short life span for the new steam boiler with the very hard water you have there.

Another option you should explore is the possibility of installing a water softener system in the cellar where the water supply comes into the house---this could minimize the damage being done to the steam system.

These issues are very difficult, if not impossible to resolve over the internet---as a first step, I would recommend you get several on-site estimates from heating contractors as to the feasibility of a full conversion to forced hot water heating with baseboards or radiators as the way to go.

Was it ever determined that you have a one-pipe steam system or a 2-pipe steam system??? (One-pipe systems have one pipe going to each radiator, with an air valve on the other end).

If you have a 2-pipe steam system, you might well be able to retain the radiators and piping system you have now, which would make the conversion much less expensive, with the purchase of a gas-fired hot water boiler, and an indirect hot water heater.

As noted in the previous posts, forced hot water would allow you to "zone off" many sections of the house with their own thermostats & thus save lots of fuel; there is much less daily and weekly maintenance connected with forced hot water, and FHW is more tolerant of hard water issues.

A forced hot water system would also be a much stronger selling point when it came time to sell the property.

Re: Ccoverting oil steam boiler to gas, and what else?

Thank you so much for your thoughts. No, I don't know if we have a one-pipe or a two-pipe steam system. Is this something I could determine myself, if I knew what to look for? I'd love to keep our old radiators. We love the look, and they are in keeping with the style of the house.

After my last posts, we added more insulation to the house -- blown-in cellulose, and a heck of a lot of it. Our heating bills did not go down, but at a time of $147 a barrel oil, they didn't go up that much, either. So it clearly helped. This summer, we replaced about three-quarters of the windows in the house with highly insulated argon units. We keep the thermostat at 62 degrees, which makes it chilly downstairs at night and in the early morning, but the skylights in the family room (top-of-the-line insulated) and upstairs family room (not so much) keep it comfortable during the day.

We do have a water-softener system in the cellar, but I'm not convinced it's doing the job. It takes salt crystals, and I do keep the salt tank filled up, but it's an old system that was in the house when we bought it.

Why is forced hot water better than steam radiators? Isn't there a cost of electricity with that, as opposed to using the laws of physics to let steam rise and cooled water fall? Years ago I lived in a house with gas-fired gravity heat and adored it, although it rendered much of the basement unusable because of the duct work. It was cheap, too.

Zoned heat is an attractive option, of course, because we don't use much of the house in the winter. Would it be terribly expensive to install all those thermostats? I assume those would require wiring, which in our house, with the plaster walls and minimal wiring, might be a bit costly.

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